We have 2 ways to send DDoS attacks by Avalanche.
(1) DDOS feature under port table.
i) Enable DDoS under client port table, and do necessary configuration under DDoS.
ii) Enable DDoS under Run-->Configure
Note: DDoS is a history feature as it is, no bug fixed on it.
It can get 2.13Gbps SYN flood with 4425k pps with 1 3100B 10G port(3 cores).
(2) ThreatEx feature in action list.
It can get 860Mbps SYN flood with 1 3100B 10G port(3 cores).
Note: Both DDoS and ThreatEx will need license.